Heat Transfer Heat transfer efficiency leading of energy conservation in a heat exchanger can be achieved by Enhancing the fluid pumping rate Keeping the heat transfer surface clean None of these Increasing the tube length Enhancing the fluid pumping rate Keeping the heat transfer surface clean None of these Increasing the tube length ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer A 10 cm dia steam pipe, carrying steam at 180°C, is covered with an insulation (conductivity = 0.6 W/m.°C). It losses heat to the surroundings at 30°C. Assume a heat transfer co-efficient of 0.8 W/m².°C for heat transfer from surface to the surroundings. Neglect wall resistance of the pipe and film resistance of steam. If the insulation thickness is 2 cms, the rate of heat loss from this insulated pipe will be Less than the steam pipe with 5 cms insulation Less than that of the uninsulated steam pipe Greater than that for uninsulated steam pipe Equal to that of the uninsulated steam pipe Less than the steam pipe with 5 cms insulation Less than that of the uninsulated steam pipe Greater than that for uninsulated steam pipe Equal to that of the uninsulated steam pipe ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer In Biot number, the characteristic length used is the ratio of the __________ of the solid. Surface area to volume Volume to surface area Surface area to perimeter Perimeter to surface area Surface area to volume Volume to surface area Surface area to perimeter Perimeter to surface area ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer Nusselt number is the ratio of the Temperature gradient of the wall to that across the entire pipe None of these Heat flux at the wall to that across the entire pipe Temperature difference to the temperature gradient at the wall Temperature gradient of the wall to that across the entire pipe None of these Heat flux at the wall to that across the entire pipe Temperature difference to the temperature gradient at the wall ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer Convective heat transfer co-efficient in case of fluid flowing in tubes is not affected by the tube length/diameter ratio, if the flow is in the __________ zone. transition None of the listed here highly turbulent laminar transition None of the listed here highly turbulent laminar ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer For concentrating an aqueous solution of a material like anhydrous Na₂SO₄, whose solubility decreases with rise in temperature, the most suitable evaporator is a __________ evaporator. Vacuum High pressure Backward feed None of these Vacuum High pressure Backward feed None of these ANSWER DOWNLOAD EXAMIANS APP